The last half of 2000 was marked by a troubling jump in delinquencies on subprime mortgages, and some analysts are fingering an economic slowdown as the culprit. "While any [increases] in delinquencies were modest, it does represent a reversal from the pronounced declines enjoyed in the first nine months of 2000," said Rod Dubitsky, a vice president for mortgage-related ABS at Credit Suisse First Boston in an analysis of fourth quarter trends.